Device for radially centering turbine housings

ABSTRACT

In order to attain an axially fixed mounting of the inner shell of a turbomachine housing in the vicinity of the bearing and centering locations of a respective, axially-normal plane, a pocket space of a groove widening provided in an axial groove formed in the outer shell of the housing is located, as viewed from the outside, axially behind a respective retaining claw received in the axial groove and is formed by a reduction of the narrower axial groove with respect to the groove widening. Another fitting member in form of a cross bar is insertable into the pocket space, rearwardly engages the retaining claw and abuts axially against housing shoulders located in vicinity of a bottom surface of the pocket space, thereby fixing the inner shell against displacement in one axial direction. The inner shell is formed with annular surfaces abuttable against corresponding annular shoulder-countersurfaces formed on the outer shell, thereby fixing the inner shell against displacement in the other axial direction.

United States Paten 1191 Remberg [11] 3,754,833 1451 Aug. '28, 1973DEVICE FOR RADIALLY CENTERING TURBINE HOUSINGS Primary Examiner-C. J.Husar {75] Inventor: Axel Remberg, Mulheim, Germany Attorney-HerbertLerner et [73] Assignee: Kraftwerk Union Aktiengesellschatt, 57]ABSTRACT Mulhelm Germany In order to attain an axially fixed mounting ofthe inner [22] Filed: Apr. 17, 1972 shell of a turbomachine housing inthe vicinity of the [2!] App] No 244 416 bearing and centering locationsof-a respective, axiallynormal plane, a pocket space of a groovewidening provided in an axial groove formed in the outer shell of the[30] Foreign Application Priority Data housing is located, as viewedfrom the outside, axially Nov. 5, 1970 Germany p 2 5 4654 behind arespective retaining claw received in the axial groove and is formed bya reduction of the narrower 52 as. C] 415/108, 415/134, 415/136, axialgroove with respect to the groove widenihs- 4 5 2 415/219 other fittingmember in form ofa cross bar is insertable 511 1111. C1. F0ld 25/26 intothe Pocket Space rearwardly engages the retaining [58] Fleld of Search415/108, 134, I36, claw and fibula axially against housing shoulders415/142, 219 cated in vicinity of a bottom surface of the pocket 1space, thereby fixing the inner shell against displace- [56 R fe nCitedmentin one axial direction. The inner shell is formed UNITED STATESPATENTS with annular surfaces abuttable against corresponding annularshoulder-countersurfaces formed on the outer glg a s shell, therebyfixing the inner shell against displace- 3:628,878 12/1971 Trassei et415/108 m the (her 8 Claims, 5 Drawing Figures lib 3a32bl5ba410911 6 1b11 I r1 r2 2c 3 i r1;r2

l A 7 21a la I A 21a 19; I k I I 4 1 L11 L 3b Z 15 M) I Patented Aug.28, 1973 3,754,833

2 Sheets-Sheet l Patented Aug. 28, 1973 3,754,833

2 Sheets-Sheet z DEVICE FOR RADIALLY CENTERHNG TURBINE llllOUSlNGS Theinvention relates to a device for radiallycentrally, thermallydisplaceably mounting and centering inside housing shells relative tooutside housing shells in turbomachines and, more particularly steamturbines, having at least three, but preferably fourbearing andcentering locations disposed in an axially normal plane and symmetricalto the major transverse axes of the turbomachines. The inner shell whichis insertable axially into the outer shell, that has a pot-likeconstruction, is provided at the outer periphery thereof in the vicinityof the bearing and centering locations, with radially protrudingretaining claws while the outer shell is provided, at respectivelocations of the inner periphery thereof, with axial grooves whichaccommodate the retaining claws. The axial grooves are formed, on bothlongitudinal sides of the retaining claws, with peripherally extendinggroove widenings located between first, axially extending fittingsurfaces of the retaining claws and second axially extending fittingsurfaces of the axial grooves and located in spaced relationship to thefirst surface, fitting members in form of axially insertablelongitudinally extending bars being receivable in the groove widenings.

Such a device is basically known from German Published Application DASl,0l8,07l. The advantages thereof is its rugged construction and theavoidance of ruptures in the outer housing. The heretofore-known devicedoes not, however, afford axial fixation of the inner shell with respectto the outer shell; this axial fixing, as is well known, is required atone end of the inner shell in order to attain a defined set point orfixed point wherefrom the axial housing-expansions can proceed.

It is accordingly an object of the invention to provide a device of theforegoing type with axial fixing means which are of rugged constructionand relatively easy to assemble as well as dismantle.

With the foregoing and other objects in view, there is thereforeprovided, in accordance with the invention, device forradially-centrally, thermally displaceably mounting and centering aninner shell of a turbomachine housing relative to a pot-shaped outershell thereof, the inner shell being axially insertable into the outershell, including at least three bearing and centering locations disposedin an axially normal plane and symmetrical to the major transverse axesof the turbomachine, retaining claws radially extending from the outerperiphery of the inner shell in vicinity of the bearing and centeringlocations, the outer shell being formed at corresponding locations ofthe inner periphery thereof with axial grooves wherein the retainingclaws are receivable, the axial grooves being formed on oppositelongitudinally extending sides of the retaining claws, with peripherallyextending groove widenings located between first axially extendingfitting surfaces of the retaining claws and second axially extendingfitting surfaces of the axial grooves and located in spaced relationshipto the first surfaces, fitting members in form of axially insertablelongitudinally extending bars receivable in the groove widenings, and,to mount the inner shell in the vicinity of the bearing and centeringlocations of the respective axially normal plane, including a pocketspace of the groove widening located, as viewed from the outside,axially behind the respective retaining claws and formed by a reductionof the narrower axial groove with respect to the groove widening,

and another fitting member in form of a crossbar insertable into thepocket space and rearwardly engaging the retaining claw and abuttingaxially against housing shoulders located in vicinity of a bottomsurface of the pocket space, whereby the inner shell is fixed againstdisplacement in one axial direction, the inner shell being formed withannular surfaces abuttable against corresponding annularshoulder-countersurfaces formed on the outer shell whereby the innershell is fixed against displacement in the other axial direction.

The advantages afforded by the invention of this application lieprimarily in the fact that the bearing and centering locations canabsorb considerable forces and, nevertheless, permit a very exact andconfortable adjustment. The device is of such rugged and stableconstruction that the shaft sealing casings, for example, can get bywith only one axially normal bearing and centering location plane at oneof the ends thereof, while the other end thereof can project freely,axially and radially displaceably, into the steam chamber or interiorspace of the outer housing of the steam turbine. This is effected, in adesirable manner, by the insertion of the outer shell between theannular surfaces of the inner shell and the annularshoulder-countersurfaces. This construction can be further improved, asa result of the use of slide rings that are disposed, on the one hand,in annular grooves of the inner shell and, on the other hand, of theouter shell. The slide rings can be made of a stell possessingparticularly advantageous sliding properties and having an especiallyprecise construction.

In accordance with another feature of the invention, the fittingsurfaces of the retaining claws are respectively formed as axialretaining grooves wherein the longitudinally extending fitting membersare fittable with matching countersurfaces of correspondingly equalradial dimension so that a respective sliding surface pair is formed bythe fitting surface of the groove widening and the fittingcountersurface of the longitudinally extending bar in engagementtherewith, the

cross-bar of the respective retaining claws beingsecured in position byform-locking engagement with both longitudinally extending bars wherebythe longitudinally extending bars, in turn, are secured against fallingout in axial direction. This security against falling or slipping out inaxial direction is provided for the longitudinal bars, as noted morefully herein below principally by providing the longitudinal bars withsquaredoff surfaces at their outer end which abut with the outer endface of the retaining claw, and tightly bolted or screwed thereto. Thistight bolting in the vicinity of the squared-off surfaces can bedispensed with, however, if the longitudinal bars are flush at theirfree end faces, with the front end faces of the pot-shaped outerhousing, so that the outer sealing cover, which is mounted on these endfaces, can simultaneously assume the form-locking securing of thelongitudinal bars.

if it is desired that the slot between the head of the retaining clawsand the inner periphery of the outer shell should not be too large, inaccordance with another feature of the invention with respect to theinsertion of the crossbars into their respective pocket spaces, in theperipheral region located between the retaining claws, and annular slot,between the outer periphery of the inner shell and the inner peripheryof the outer shell, the annular slot being of such radial width and suchaxial extension that the respective crossbar is axially insertable intothe same and is slideable in peripheral direction into a peripheralangular region of the pocket space located axially behind the retainingclaw, the crossbar, in the peripheral angular region, being displaceablein radial direction within the pocket space located axially behind theretaining claw so as to be engageable, on the one hand, with housingshoulders located at the bottom of the pocket space and, on the otherhand, with the rear, axially-normal end face of the retaining clawwhereby the retaining claw is secu rable in this position againstfalling out.

In accordance with the preferred usage of the invention, the inner shellis an axially subdivided shaft sealing casing, and the outer shell is anouter housing of a steam turbine, the bearing and centering locationsbeing disposed at the cold end of the shaft sealing casing which isaccessible from the outside, the hot end of the shaft sealing casingextending into the inner space of the outer housing and being axiallyand radiallycentrally, thermally displaceable therein.

In accordance with yet another feature of the invention, theform-locking position-fixing of the longitudinal bars and the crossbarsis achieved by including an axially subdivided sealing cover seatable onan axiallynormal annular surface of the outer end wall of the outerhousing containing the bearing and centering locations whereby thelongitudinally extending bars are secured against falling out.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin device for radially-centrally, thermally displaceably mounting andcentering inner housing shells with respect to the outer housing shellsof turbomachines, particularly steam tubines, it is nevertheless notintended to be limited to the details shown, since various modificationsand structural changes may be made therein without departing from thespirit of the invention and within the scope and range of equivalents ofthe claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings, in which:

FIG. 1 is a longitudinal sectional view of a steam turbine of axialconstruction with an outer housing constructed as a pot housing providedat both ends thereof with the bearingand centering device of theinvention;

FIG. 2 is a transverse view along the plane represented by the linelI-II in FIG. I, the flange portion of the outer housing being omittedand the longitudinal bar being a modification of that of FIG. I by beingbevelled at the outer ends thereof;

FIG. 3 is an enlarged fragmentary view of FIG. 1 showing the detailenclosed in the circle A;

FIG. 4 is a view in direction of the arrow E. in FIG. 3, wherein theinsertion maneuver of the crossbar is indicated; and

FIG. 5 is a sectional view of FIG. 3 taken along the line V-V inperipheral direction.

The high-pressure partial turbine of axial construction according toFIG. 1 is shown in simplified form, the section lines being omitted. Theturbine is made up of the following main parts: the shaft l, the blading2 with rotor blade crowns 2a at the outer periphery of the shaft 1 andguide vane crowns 2b at the inner periphery of the inner shell 3 thatencloses the shaft. The shell 3 is constructed as an axially divided,combined guide vane carrier-inner housing having a pair of shell halves3a and 3b as well as a vertical joint or seam 30 (see FIG. 2). Othermain parts of the turbine are an outer housing 4 with a pot-like portion4a and a cover portion 4b, as well as ajoint or seam 4c extending indirection normal to the axis of the turbine; two shaft sealing casings 5and 6 that are sub-divided in axial direction and located in the regionwhere the shaft extends out of the outer housing 4 into the surroundingspace; sealing covers 7 and 8 also sub-divided in axial direction andmounted upon the shaft-sealing casing 5 and 6, respectively, as well asanother sealing casing 9, which is surrounded by the inner housing shell3 and seals the live-steam room 10 from a casing chamber 11 locatedbetween the inner and the outer shells 3 and 4. The inner shell 3 isprovided with an annular collar 3a with which it bears steam-tightlyagainst the outer housing and the vicinity of a bearing and centeringlocation 12 thereof,and is radially-centrally, thermally displaceableand axially fixed. The bearing between the shells 3 and 4 is furthereffected in a manner which is not of any further interest with respectto the invention of this application, by the insertion of a sealingU-ring 12a, and retaining ring 12b, as well as the supporting ring 12c.The steam passes from the live-steam inlet 10 through the blading 2, toa space 13 located at the discharge end of the turbine and from therethrough an exhaust pipe 14 to a non-illustrated, after-connectedintermediate pressure turbine stage or intermediate superheater. By-passchannels 15 help to keep the space I] at an intermediate pressure.Flange screws 16 are provided for connecting the outer housing portions4a and 4b at the axially-normal joint 4c. The rotor blading 2a iscarried by a shaft portion la. The shaft 1 is also provided with anequalizing piston portion lb. Sealing or packing segments 17 are locatedat the inner periphery of the shaftsealing casings 5, 6 and 9 andsealing covers 7 and 8, and are subdivided in peripheral direction.These sealing segments 17 form labyrinths with corresponding opposingsurfaces located at the outer periphery of the shaft 1. By-pass channels18 are formed in the shaftsealing casings S and 6 for attaining definedpressure differences between annular spaces located in succession at theouter periphery of the sealing casings and sealed by U-rings 19.

The invention will first be described with reference to theshaft-sealing casing 6 with the sealing cover 8. Both sealing casinghalves 6a and 6b (FIG. 2), which are clamped together by flange screws60! in the region of the joint 60, are provided with four bearingandcentering locations z located in a plane disposed normally to theaxis of the turbine and symmetrical to the main transverse axes v and hof the steam turbine. The bearing and centering locations 2 areindividually identified as zl, Z2 (horizontal transverse axis h) and 23,24 (vertical transverse axis v). The shaft-sealing casing 6, which isaxially insertable into the outer housing 4 is provided at the outerperiphery thereof in the vicinity of the bearing and centering locationsz, with respective radially projecting retaining claws k. The outerhousing 4 is provided, at appropriate locations of the inner peripherythereof, with axial grooves n for respectively accommodating theretaining claws k therein (note FIGS. 3 and 5). On both longitudinallyextending sides of the retaining claws k peripherally extending grooveenlargements or widenings n,. are formed between first axially extendingfitting surfaces [1 of the retaining claws k and second axiallyextending fitting surfaces/2 of the axial grooves n located in spacedrelationship opposite the first surfaces fl. The groove enlargements nare capable of receiving therein fitting parts in the form of axiallyinsertable longitudinally extending bars I.

As is shown particularly in FIGS. 3 and 5, in order to obtain an axiallyfixed bearing support for the shaftsealing casing 6 in the region of thebearing and centering locations 1 of the respective axially-normalplane, a pocket space t of the groove enlargement or widening n, islocated, as viewed from the outside, axially behind the respectiveretaining claw k, and is formed by reducing the narrower axial groove nwith respect to the groove enlargement n Into this pocket space t,another fitting member q in form of a crossbar is insertable and, asseen in FIGS. 3 and 5, the crossbar rearwardly engages the retainingclaw k and abuts axially against the housing shoulders t], in thevicinity of the bottom of the pocket t, thereby fixing the shaft-sealingcasing 6 against displacement in the one axial direction. The shaftsealing casing 6 is fixed against displacement in the other axialdirection by the fact that it abuts with annular surfaces r1 thereofagainst correspondingannular shoulder-counter surfaces r2 of the outerhousing 4. Rings r3, r4 are inserted between the annular surfaces rl andthe annular shoulder countersurfaces r2 to effect a more exact axialfixation of the casing 6 and to improve the slideability thereof inradial direction.

The matching or mutually fitting surfaces fl of the retaining claws kare formed as axial retaining grooves, respectively, as'shownparticularly in FIGS. 2 and 4, into which the longitudinal bars I withopposite fitting surfaces l of the same radial dimension can be fitted.The respective pair of slide surfaces in the vicinity of the bearing andcentering locations z, is formed by the fitting surface f2 of the grooveenlargementor widening n and the adjcent opposite fitting surface 1 ofthe longitudinal bar I. The crossbar q of the respective retaining clawk is secured in its position by form-locking engagement therewith ofboth longitudinal bars I (note especially FIG. 5). To this end, thelongitudinal bars I are provided with a step-like offset at the end 1;,thereof that engages the cross-bar q and in the inserted position of thebars 1, they grip with the crossbar q by the step section 1 thereof(FIG. 3). The longitudinal bars I, in the embodiment of FIG. 2, are, inturn, securable against slipping out in axial direction, by beingscrewed, with squared-off surfaces I located at the free end thereof, tothe retaining claws k. The position of the fastening or securing screwsand the appertaining threaded bores is indicated in FIG. 2 at 20.According to FIG. I as well as FIGS. 3 to 5, this securing means mayalso be realized by a form-locking device wherein the aforementionedaxially sub-divided sealing cover 8 is mounted upon an axially-normalannular surface 21 of the outer end wall 4d of the outer housing 4 whichcontains the bearing and centering location arangement z, the sealingcover 8 establishing with an inner annular surface 21a thereof a flushfitting contact with the outer end of the longitudinal bars 1. FIG. 5shows one longitudinal bar I not yet in the inserted condition thereof,and the arrow 22 indicates the direction of insertion.

A particularly advantageous possible manner of inserting the crossbars qis shown in FIG. 4 in connection with FIGS. 3 and 5. As illustratedtherein, in the peripheral region located between the retaining claws k,there is provided, between the outer periphery of the casing 6 and theinner periphery of the outer housing 4, an annular slot 23 of suchradial width 23a and such axial extension 2312 (FIG. 3), that therespective crossbars q, shown in FIG. 4 in dotted lines, is axiallyinsertable into the annular slot 23 and is slideable in peripheraldirec-' tion into the peripheral angular region or sector 23c of thepocket space 1, which is located axially behind the retaining claw k. Inthis peripheral angular region 23c, the crossbar q (note the arrow 24indicating the displacement direction), by displacement in radialdirection within the pocket space t located axially behind the retainingclaw k, may be brought into engagement, firstly, with the housingshoulders t1 of the bottom of the pocket t, and secondly, with the rear,axiallynormal end face kl of the retaining claw k. To effect thisdisplacement maneuver for the crossbar q,the latter is provided, atleast at one end thereof, with an outwardly directed threaded bore qlinto which a bar is threadedly insertable. After the cross bar q isplaced into its final position shown in solid lines in FIGS. 3 and 5, itis form-locki'ngly secured in this position by inserting thelongitudinal bars I, as described hereinbefore. The longitudinal bars I,which are in flush alignment with the end wall surface 21 of the outerhousing 4 for the purpose of securing by means of the sealing cover 8,are provided, at the outwardly directed end thereof with a threaded bore1 as shown in FIG. 4 for threadedly inserting therein a rod or bar inthe event they are to be dismantled or disassembled.

As shown by the full view of FIG. I, the bearing and centering locationsz are disposed at the cold end of the shaft-sealing casing 6 which isaccessible from the outside. The hot end of the shaft-sealing casing 6which extends into the interior space ill of the outer housing 4, ismounted so as to be axially and radially centrally, thermallydisplaceable with the insertion of the U- shaped sealing ring 19. Thethermal expansions in axial direction therefore proceed from the axiallynormal plane of the bearing and centering locations 2, in directiontoward the interior of the housing. In addition to being in sealingengagment with the outer housing 4, the sealing cover 8 also maintainssealing engagement with the shaft-sealing easing 6, namely through theinsertion of another U-shaped sealing ring 19a.

As is apparent, furthermore, the shaft-sealing casing 6 is mounted, byits bearing and centering device z, in the vicinity of the passagethrough which the shaft 1 extends, at the end wall 4d of the hot end,that forms the bottom of the pot-shaped portion 4a of the outer housing.Assembly is effected in a manner that the turbine rotor I provided withthe shells 6a and 6b of the shaftsealing casing 6 is insertable invertical direction into the pot-shaped housing part 40, the casing 6abutting with its shoulder surfaces rll against the annular countersurfaces r2 of the outer housing 4.

The longitudinal bars I and the cross bars q of the retaining claws kcan then be inserted from the outside,into the groove enlargements orwidenings n. and q t of the end wall 4d, and the sealing cover 8 can beplaced the'reover.

The arrangement of the bearing and centering locations at the left endof the turbine shown in FIG. 1, for

the shaft-sealing casing and the sealing cover 7, is provided in asimilar manner, and like or corresponding parts are identified by thesame reference numerals. There is a difference insofar as theshaft-sealing casing 5 is mounted in the vicinity of the passage throughwhich the shaft 1 extends out of the housing 4, atthe end wall of thecold end of the turbine, forming the pot cover 4b and, consequently,upon assembly, the pot cover 4b formed with the groove enlargements orwidenings n, and t is slipped over the shaft 1, which is provided withthe shaft sealing casing 5. The pot cover 4b, with its annularcountersurfaces r2, thereby abuts against the annular shoulder surfacesr1 of the sealing casing 5. The weight of the pot cover 4b, is absorbedthough in the region of the axially-normal joint 40. As describedhereinbefore in connection with the shaftsealing casing 6, thelongitudinal bars I and the crossbars q are insertable from the outsideinto the groove enlargements or widenings n, and t, and the sealing lid7 is placeable thereover.

Although the illustrated embodiments of the bearing and centeringarrangement at shaft-sealing casings are particularly preferred, it isunderstood that the principle of the invention is applicable for bearingand centering accompanied by fixation against axial displacement withrespect to turbine-housing inner shells, i.e. inner housings or casings,and/or guide-vane carriers.

I claim:

1. Device for radially-centrally, thermally displaceably mounting andcentering an inner shell of a turbomachine housing relative to apot-shaped outer shell thereof, the inner shell being axially insertableinto the outer shell, comprising at least three bearing and centeringlocations disposed in an axially normal plane and symmetrical to themajor transverse axis of the turbomachine, retaining claws radiallyextending from the outer periphery of the inner shell in vicinity ofsaid bearing and centering locations, the outer shell being formed atcorresponding locations of the inner periphery thereof with axialgrooves wherein said retaining claws are receivable, said axial groovesbeing formed, on opposite longitudinally extending sides of saidretaining claws, with peripherally extending groove widenings locatedbetween first axially extending fitting surfaces of said retaining clawsand second axially extending fitting surfaces of said axial grooves andlocated in spaced relationship to said first surfaces, fitting membersin form of axially insertable longitudinally extending bars receivablein said groove widenings, and, to mount the inner shell in the vicinityof said bearing and centering locations of the respective axially normalplane, including a pocket space of said groove widening located, asviewed from the outside, axially behind the respective retaining clawand formed by a reduction of the narrower axial groove with respect tosaid groove widening, and another fitting member in form of a cross-barinsertable into said pocket space and rearewardly engaging saidretaining claw and abutting axially against housing shoulders located invicinity of a bottom surface of said pocket space, whereby said innershell is fixed against displacement in one axial direction, said innershell being formed with annular surfaces abuttable against correspondingannular shoulder-countersurfaces formed on the outer shell whereby saidinner shell is fixed against displacement in the other axial direction.

2. Device according to claim 1 wherein said fitting surfaces of saidretaining claws are respectively formed as axial retaining grooveswherein said longitudinally extending fitting members are fittable withmatching countersurfaces of correspondingly equal radial dimension sothat a respective sliding surface pair is formed by said fitting surfaceof said groove widening and the fitting countersurface of saidlongitudinally extending bar in engagement therewith, the crossbar ofthe respective retaining claws being secured in position by form-lockingengagement with both longitudinally extending bars whereby saidlongitudinally extending bars, in turn, are secured against falling outin axial direction.

3. Device according to claim 2 wherein said longitudinally extendingbars are formed, at the end thereof engaging said cross bar, with astep-like offset with which said cross bar is gripped.

4. Device according to claim 1 including, in the peripheral regionlocated between said retaining claws, an annular slot, between the outerperiphery of said inner shell and the inner periphery of said outershell, said annular slot being of such radial width and such axial.extension that the respective crossbar is axially insertable into thesame and is slideable in peripheral direction into a peripheral angularregion of said pocket space located axially behind said retaining claw,said crossbar, in said peripheral angular region, being displaceable inradial direction within said pocket space located axially behind saidretaining claw so as to be engageable, on the one hand, with housingshoulders located at the bottom of said pocket space and, on the otherhand, with the rear, axially normal end face of said retaining clawwhereby said retaining claw is securable in this postion against fallingout.

5. Device according to claim 1 wherein said inner shell is an axiallysubdivided shaft sealing casing, and said outer shell is an outerhousing of a steam turbine, said bearing and centering locations beingdisposed at the cold end of said shaft sealing casing which isaccessible from the outside, the hot end of said shaft sealing casingextending into the inner space of said outer housing and'being axiallyand radially-centrally, thermally displaceable therein.

6. Device according to claim 5 including an axially subdivided sealingcover seatable on an axially-normal annular surface of the outer endwall of said outer housing containing said bearing and centeringlocations whereby said longitudinally extending bars are secured againstfalling out.

7. Device according to claim 6 wherein said shaft sealing casing ismounted, by its bearing and centering locations in vicinity of a passagethrough which the turbine shaft extends to the outside, at the end wallof the hot end which forms the bottom of a pot-shaped porhousing, saidlongitudinal bars and crossbars of said retaining claws beinginsertablefrom the outside into said groove widenings of said end wall, and saidsealing cover being seatable thereover.

8. Device according to claim 6 wherein said shaft sealing casing ismounted, by its bearing and centering nular counter surfaces providedthereon with annular shoulder surfaces formed on said shaft sealingcasing. said longitudinally extending bars and said crossbars beinginsertable from the outside into said groove widenings, and said sealingcover being seatable thereover.

1. Device for radially-centrally, thermally displaceably mounting andcentering an inner shell of a turbomachine housing relative to apot-shaped outer shell thereof, the inner shell being axially insertableinto the outer shell, comprising at least three bearing and centeringlocations disposed in an axially normal plane and symmetrical to themajor transverse axis of the turbomachine, retaining claws radiallyextending from the outer periphery of the inner shell in vicinity ofsaid bearing and centering locations, the outer shell being formed atcorresponding locations of the inner periphery thereof with axialgrooves wherein said retaining claws are receivable, said axial groovesbeing formed, on opposite longitudinally extending sides of saidretaining claws, with peripherally extending groove widenings locatedbetween first axially extending fitting surfaces of said retaining clawsand second axially extending fitting surfaces of said axial grooves andlocated in spaced relationship to said first surfaces, fitting membersin form of axially insertable longitudinally extending bars receivablein said groove widenings, and, to mount the inner shell in the vicinityof said bearing and centering locations of the respective axially normalplane, including a pocket space of said groove widening located, asviewed from the outside, axially behind the respective retaining clawand formed by a reduction of the narrower axial groove with respect tosaid groove widening, and another fitting member in form of a cross-barinsertable into said pocket space and rearewardly engaging saidretaining claw and abutting axially against housing shoulders located invicinity of a bottom surface of said pocket space, whereby said innershell is fixed against displacement in one axial direction, said innershell being formed with annular surfaces abuttable against correspondingannular shoulder-countersurfaces formed on the outer shell whereby saidinner shell is fixed against displacement in the other axial direction.2. Device according to claim 1 wherein said fitting surfaces of saidretaining claws are respectively formed as axial retaining grooveswherein said longitudinally extending fitting members are fittable withmatching countersurfaces of correspondingly equal radial dimension sothat a respective sliding surface pair is formed by said fitting surfaceof said groove widening and the fitting countersurface of saidlongitudinally extending bar in engagement therewith, the crossbar ofthe respective retaining claws being secured in position by form-lockingengagement with both longitudinally extending bars whereby saidlongitudinally extending bars, in turn, are secured against fallIng outin axial direction.
 3. Device according to claim 2 wherein saidlongitudinally extending bars are formed, at the end thereof engagingsaid cross bar, with a step-like offset with which said cross bar isgripped.
 4. Device according to claim 1 including, in the peripheralregion located between said retaining claws, an annular slot, betweenthe outer periphery of said inner shell and the inner periphery of saidouter shell, said annular slot being of such radial width and such axialextension that the respective crossbar is axially insertable into thesame and is slideable in peripheral direction into a peripheral angularregion of said pocket space located axially behind said retaining claw,said crossbar, in said peripheral angular region, being displaceable inradial direction within said pocket space located axially behind saidretaining claw so as to be engageable, on the one hand, with housingshoulders located at the bottom of said pocket space and, on the otherhand, with the rear, axially normal end face of said retaining clawwhereby said retaining claw is securable in this postion against fallingout.
 5. Device according to claim 1 wherein said inner shell is anaxially subdivided shaft sealing casing, and said outer shell is anouter housing of a steam turbine, said bearing and centering locationsbeing disposed at the cold end of said shaft sealing casing which isaccessible from the outside, the hot end of said shaft sealing casingextending into the inner space of said outer housing and being axiallyand radially-centrally, thermally displaceable therein.
 6. Deviceaccording to claim 5 including an axially subdivided sealing coverseatable on an axially-normal annular surface of the outer end wall ofsaid outer housing containing said bearing and centering locationswhereby said longitudinally extending bars are secured against fallingout.
 7. Device according to claim 6 wherein said shaft sealing casing ismounted, by its bearing and centering locations in vicinity of a passagethrough which the turbine shaft extends to the outside, at the end wallof the hot end which forms the bottom of a pot-shaped portion of saidouter housing, the rotor of the turbine provided with shells of saidshaft sealing casing being insertable in vertical direction into saidpot-shaped outer housing portion, said shaft sealing casing havingshoulder surfaces with which it is in abutting engagement with annularcountersurfaces formed on said outer housing, said longitudinal bars andcrossbars of said retaining claws being insertable from the outside intosaid groove widenings of said end wall, and said sealing cover beingseatable thereover.
 8. Device according to claim 6 wherein said shaftsealing casing is mounted, by its bearing and centering locations invicinity of a passae through which the turbine shaft extends to theoutside, at the end wall of the cold end of the turbine, which forms acover portion of said outer housing, said cover portion being formedwith said groove widenings and being slideable over the shaft which isprovided with said shaft sealing casing so that said cover portion is inabutting engagement by annular counter surfaces provided thereon withannular shoulder surfaces formed on said shaft sealing casing, saidlongitudinally extending bars and said crossbars being insertable fromthe outside into said groove widenings, and said sealing cover beingseatable thereover.